1. Field of the Invention
The present invention relates to keel coolers. More particularly, the present invention relates to a system for insuring that a keel cooler is properly sealed to the hull of a vessel, and compensating for any misalignment in the openings in the vessel hull and the nozzles on the keel cooler using bushings having eccentric wall thicknesses.
2. General Background
Keel coolers have been used for decades as a device for cooling a vessel's engine water in order to prevent the engine from overheating. The most common type of keel cooler, and one which has dominated the industry for decades, is a keel cooler manufactured by R. W. Fernstrum & Company, and which was the subject of U.S. Pat. No. 2,382,218 issued on Aug. 14, 1945. That keel cooler which is currently being sold today provides a heat exchanger portion positioned between a pair of header portions, each header having a threaded pipe connection for connecting onto the water cooling system of a vessel's engine when the keel cooler is secured to a marine hull structure. The keel cooler heat exchanger portion includes a plurality of parallel heat conduction tubes extending between the headers, so that as heated engine water enters into a first threaded pipe through the first header, the water travels through the plurality of spaced apart heating tubes. The heating tubes are submerged in the water in which the vessel is moored, so that as the hot engine water runs through the headers and the tubes, it exits through the second header, having exchanged a great deal of heat from the engine water into the surrounding ambient water. This type of heat exchanger is a very efficient, compact and dependable heat exchanger, hence its industry dominance for the past fifty years.
In mounting keel coolers to vessel hulls ideally the openings in the hull are precisely spaced so as to engage in fluid tight engagement the nozzles of the keel cooler being mounted. However, through human error, often times the openings are a millimeters off in spaced apart alignment, so that when the nozzles are inserted, there is less than a fluid tight fit, which creates leakage and other problems in setting the alignment straight. Therefore, there is a need in the industry to solve this very common problem.